Such a material is, for example, mineral wool, which has to be separated into commercially customary sheets for shipping.
Insulating materials comprising mineral wool consist of vitreously solidified mineral fibers which are joined together in principle at discrete points by small amounts of a binder, usually a thermosetting plastic. The mineral fibers are obtained from a melt which is fiberized in a fiberizing unit. It is common commercial practice to distinguish between insulating materials comprising glass wool and rock wool.
Glass wool fibers are produced from silicate melts with relatively high alkali content, optionally also boroxides, by passing the melt through the fine openings in the wall of a rotating body. This creates relatively long and smooth mineral fibers, which are provided with binders and impregnating agents and fall onto an air-permeable transporting belt.
An endless fiber web drawn off from the fiberizing units is transported away at a greater or lesser speed, depending on the desired thickness and apparent density. The curing of the binder fixing the structure of the insulating material to be produced takes place in a curing oven, in which hot air is passed through the fibrous web. Subsequently, the cured fibrous web is trimmed at the sides and, for example, divided in the middle into two webs, from which sheets of insulating material of a certain length and any desired widths, within the limits of the width of the web, can be separated with hardly any loss.
Insulating materials comprising rock fibers, in particular sheets of insulating material comprising rock fibers, are less readily compressible than insulating materials comprising glass fibers, since they have distinctly different structures, which are evident primarily in the tangled form of the short rock fibers, the rock fibers already aggregating into flocks on the way from the fiberizing machine to a transporting belt. The insulating materials produced from this have, for example, very narrow variations in apparent density over the width of the production line and the height of the fibrous web.
Sheets of insulating material comprising rock fibers are produced with customary dimensions of 1 m or 1.2 m in length along with a width of 0.6 m or 0.65 m and thicknesses of about 20 mm to about 240 mm.
Sheets of insulating material are produced in large quantities, and therefore first have to be divided into appropriate formats before they are ordered in stacks.
Austrian patent specification AT 104894 discloses a crank-driven pendulum saw for a comparable purpose, with a conveyor belt for displacing the material to be cut.
This saw has an adjustable device, with which the length to be cut off in each case can be precisely set. With this device, only low cycle times can be achieved for separating the material to be cut.
Swiss patent specification CH 93038 discloses a pendulum saw which is distinguished by the fact that the saw blade is suspended from a fixedly mounted rocker by means of a hanging link, so that it can be displaced in a horizontal path by swinging the hanging link back and forth on the rocker. Significant cycle times cannot of course be achieved with this solution either.
DE 198 46 946 A1 describes operating modes of point-contact pendulum saws, understood as meaning saws in which the sawing implement is made up of one or more parallel saw blades clamped in place. For this type of design, it is proposed in this document that the pendular mass, that is to say the saw frame with the saw blades, does not oscillate on a circular path but on a path that describes a double cycloid curve. However, this document does not make any reference to the construction of a pendulum saw with circular saw blades.
Recent development has been toward pendulum saws that are actuated by means of hydraulic devices, which are expensive, react relatively slowly and require sophisticated controlling operations. No printed citations as evidence of this are known.